CVE-2019-12951: Cesanta Mongoose

Critical severity, CVSS 9.8. EPSS: 2% chance of exploitation in the next 30 days.

An issue was discovered in Mongoose before 6.15. The parse_mqtt() function in mg_mqtt.c has a critical heap-based buffer overflow.

Affected products

• Cesanta Mongoose: before 6.15 (fixed in 6.15)

Published 2019-06-24. Last modified 2026-06-17.